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991.
A few halo, nitro and methoxy substituted 1:2-naphthoquinones with the substituents in both the benzenoid and the quinonoid rings have been synthesised and evaluated for their fungistatic properties. Among the quinonoid compounds tested 3:4-dichloro-1:2-naphthoquinones exhibited the highest activity. 相似文献
992.
993.
994.
The second negative bands of O 2 + , lying in the region 5000–1850 Å, have been photographed using oxygen enriched in18O. A study of the isotope shifts in the band heads revealed that thev″ numbering is to be increased by one unit whereas thev′ numbering remains unaltered. This change in vibrational numbering leads to a revision of the molecular constants of O 2 + , especially of those in its ground state. These are discussed and the extension of the band system in the vacuum ultra-violet region reported. The possibility of developing a simple spectrographic method for the isotopic assay of oxygen using the isotope shifts in this band system is pointed out. The revised rotational and vibrational constants in theX 2 II g ground state of O 2 + molecule are as follows :
$$\begin{gathered} \omega _e = 1903 \cdot 85 cm.^{ - 1} , \hfill \\ \omega _e x_e = 16 \cdot 18 cm.^{ - 1} , \hfill \\ B_e = 1 \cdot 6920 cm.^{ - 1} \hfill \\ and \hfill \\ r_e = 1 \cdot 1161 {\AA}. \hfill \\ \end{gathered} $$ 相似文献
995.
Decay of Gd153 has been studied by means of internal conversion and external conversion data, using Siegbahn-Slätis intermediate image beta-ray spectrometer. The existence of the 96 ± 2 Kev. transition in Gd153 has been established and its conversion coefficient has been determined. 相似文献
996.
997.
Bappanadu N. Rao 《Journal of Physics and Chemistry of Solids》1976,37(2):137-142
A two level two sublattice antiferromagnetic induced moment system is examined in the Green's function theory in the random phase approximation. Attentions are drawn to the effects of an externally applied magnetic field. It is shown that a “soft mode” behavior occurs at the transition field similar to that observed at the transition temperature in the absence of a field. The transition becomes first order in the RPA. The sublattice magnetizations and the transition field are significantly lowered compared to the molecular field theory results. 相似文献
998.
999.
1000.
Various platinum complexes have been studied by 195Pt FT NMR. Long range J(31P195Pt) and J(195Pt195Pt) are observed in dinuclear complexes. The value of 1J(31P195Pt) in monomeric and dimeric complexes is shown to depend mainly upon the Pt—P bond length. 相似文献